The 280pcs kit box includes: 140pcs black lock nut and 140pcs black flat washer (m3: 36pcs M4: 30pcs M5: 30pcs M6: 30pcs M8: 8pcs M10: 4pcs M12: 2pcs). Material: 304 stainless steel metric lock nut and flat gasket, with good corrosion resistance and long service life, durable, made of high-strength materials, safe to use. Widely used: used in furniture decoration, industrial production, automobile repair, machinery industry, small repair shops, buildings and other fields. Easy storage: all models and styles are classified in transparent storage boxes, which are easy to distinguish and easy to store, and can be seen at a glance. Tips: Our products are exquisitely made and packed in a beautiful box. If you have any questions during use, please contact us in time and we will deal with them as soon as possible. Ruibapa 280 PCS Black Locknuts & Flat Washer Assortment Kit, Metric Nuts and Flat Washer ( M3 M4 M5 M6 M8 M10 M12 )，304 Stainless Steel Standard Threaded Black Nylock Nuts & Flat Washers